Capacity increase and miniaturization of multilayer electronic components, e.g. multilayer ceramic capacitors (MLCC), are under way at a fast pace.
In a MLCC, ceramic green sheets including a high-dielectric material such as barium titanate, and layers formed from an electrically conductive paste mainly including an electrically conductive material, a binder resin, and a solvent, are alternately laminated in a large number and then dried and fired so as to obtain a chip with alternately laminated dielectric layers and electrode layers. Following the increase in capacity of MLCC, a demand is being created for a larger number of layers along with a reduction in the thickness of each such layer, and this is causing a variety of production problems. One particular problem is that the film strength of the electrode layers and the adhesion of the electrode layers to the dielectric material sheets have become insufficient, and this may cause some defects or result in the electrode layers peeling off from the interfaces with the dielectric layers. Further, as the particle size of the electrically conductive material is reduced, dispersivity thereof in the binder resin is degraded. The resulting problem is that the formed electrodes are not uniform, the capacity of the obtained MLCC is decreased, and an electric short circuit tends to occur more easily.
In these circumstances, a study has been conducted on the use of a mixed resin as a binder resin for an electrically conductive paste, where the mixed resin is obtained by mixing a cellulose derivative having excellent printability with a butyral-based resin or acrylic resin which excels in mechanical strength and adhesion to a green sheet [see PTL (Patent Literature) 1)]. Furthermore, using a specific solvent in addition to a well-known cellulose-based resin or an acryl-based resin in an electrically conductive paste (see PTL 2) and using a specific acrylic resin and solvent in addition to a well-known cellulose-based resin in an electrically conductive paste (see PTL 3) have also been studied.
PTL 4 also discloses the use of a mixed resin. It is indicated in this PTL that a ceramic green layer is formed so as to compensate step-like sections provided by an electrode layer formed on a green sheet, and a mixture of polyvinyl butyral and cellulose ester is used as a binder resin in a ceramic slurry of the ceramic green layer to compensate for the step-like sections (see PTL 4).